Processing system

ABSTRACT

Plural processing apparatuses  3  such as CVD apparatuses  31  and diffusion apparatuses  33 , measuring apparatuses  5 , and a control computer  7  for management are connected through a LAN  9 . Each processing apparatuses  3  stores control data for performing a treatment. The control computer  7  also stores the control data for the processing apparatuses  3 . The control computer  7  makes each processing apparatus perform a treatment for calibration. The control computer  7  receives a result of the treatment performed by the processing apparatus  3  to be calibrated, and calibrates the control data stored in the control computer  7  based on the treatment result. The control computer sends the calibrated control data to the processing apparatus  3  after completion of the calibration procedure. The processing apparatus  3  stores the calibrated control data, which is used for subsequently performed treatment.

TECHNICAL FIELD

[0001] The present invention relates to a control system and a controlmethod for processing apparatuses that treat objects such assemiconductor wafers, more particularly, to a control system and acontrol method capable of unified management of plural processingapparatuses.

BACKGROUND OF THE INVENTION

[0002] Semiconductor processing apparatuses are used for perform variouskind of treatments, such as a film deposition on a surface of asemiconductor wafer and a dopant diffusion. Processing apparatuses of astand-alone type have been primary used. In a factory equipped withplural processing apparatuses of the stand-alone type, the processingapparatuses are independently controlled based on a control program andcontrol data stored in each processing apparatus. The maintenance of theprocessing apparatuses is carried out one by one.

[0003] A control computer connected to plural processing apparatusesthrough a network to control the apparatuses is known. However, thecomputer merely gives instructions to the processing apparatuses.

[0004] Therefore, each processing apparatus must be provided with acontroller having a high computing power, resulting in increase in acost of each apparatus. In addition, the controller of the semiconductorprocessing apparatus is in need of periodical maintenance (specifically,calibration). Such maintenance must be done separately for eachapparatus, and thus is time-consuming.

DISCLOSURE OF THE INVENTION

[0005] The present invention has been made in view of the aforementionedcircumstances, and therefore the object of the present invention is tocontrol plural processing apparatuses effectively.

[0006] The second object of the present invention is to lighten the loadof control means of each processing apparatus to simplify the structureof the control means, thereby to reduce overall cost for making andoperating the processing system including plural processing apparatuses.

[0007] In order to attain the objectives, according to the presentinvention, a part of computing functions, which is possessed by thecontrol means of the conventional processing apparatus and needs a highcomputing power, is assigned to the control computer arranged separatelyfrom the processing apparatuses, thereby lightning the loads on eachprocessing apparatus.

[0008] Accordingly, the present invention provides a processing systemincluding: a plurality of processing apparatuses each includingtreatment means for treating an object, memory means for storing controldata for controlling the treatment means, and control means forcontrolling the treatment means according to the control data; and acomputer arranged separately from the processing apparatuses and adaptedto communicate data including the control data with the processingapparatuses through a communication medium, the computer includingcalibration means for calibrating the control data for controlling eachof the processing apparatuses based on a result of a treatment of theobject performed by each of the processing apparatuses inputted into thecomputer.

[0009] In one preferred embodiment, the control means of each of theprocessing apparatuses is configured to receive the control datacalibrated by the calibration means of the computer through thecommunication medium, configured to store the calibrated control data inthe memory means, and configured to perform a treatment according to thecalibrated control data.

[0010] In one preferred embodiment, the computer includes memory meansfor storing control data corresponding to each of the control datastored in the memory means of each of the processing apparatuses; andthe computer is configured to perform a procedure, when calibrating thecontrol data for one of the processing apparatuses, the procedureincluding the steps of: retrieving the control data for said one of theprocessing apparatuses stored in the memory means of the computer;calibrating the retrieved control data based on a result of a process ofthe object performed by said one of the processing apparatuses; storingthe calibrated control data in the memory means of the computer; andsending the calibrated control data to said one of the processingapparatuses through the communication medium, and making the memorymeans of said one of the processing apparatuses store the calibrateddata.

[0011] In one preferred embodiment, the processing system furtherincludes a measuring apparatus adapted to measure a result of atreatment performed by the processing apparatus, the computer isconfigured to communicate data with the measuring apparatus through thecommunication medium, whereby the result of the treatment is inputtedinto the computer through the communication medium.

[0012] In one preferred embodiment, the treatment means of each of theprocessing apparatuses includes a heating furnace adapted to heat theobject contained therein, and a plurality of thermal sensors arranged atthe heating furnace; the control data includes a model for estimatingtemperature of the object based on outputs of the thermal sensors, and arecipe defining change in temperature of the object during thetreatment; the memory means of each of the processing apparatuses isconfigured to store the model and the recipe; and the control means ofeach of the processing apparatuses is configured to estimate thetemperature of the object in the heating furnace based on the outputs ofthe thermal sensors by using the model stored in the memory means, andconfigured to control the heating furnace based on the estimatedtemperature so that the temperature of the object is coincide with atemperature defined by the recipe stored in the memory means.

[0013] In one preferred embodiment, the computer is configured toperform a procedure, when calibrating the model for one of theprocessing apparatuses, the procedure including the steps of: sending arecipe for calibrating the model to said one of the processingapparatuses; making said one of the processing apparatuses perform atreatment of the object according to the recipe for calibrating themodel; and calibrating the model by the calibration means based on aresult of the treatment of the object.

[0014] In one preferred embodiment, the computer is configured tocorrect the model based on a measurement of an actual temperature of theobject during the treatment being performed.

[0015] In one preferred embodiment, each of the processing apparatusesis configured to send a notification of a completion of the treatment ofthe object to the computer; and the computer is configured to count thenumber of treatments performed by each of the processing apparatusesaccording to the notification, and configured to calibrate the controldata at every time when a designated number of treatments has beenperformed by each of the processing apparatuses after last calibrationof the control data.

[0016] In one preferred embodiment, the processing apparatus has meansfor requesting the computer to perform a data processing; the computerincludes means for performing the data processing in response to arequest received from the processing apparatus, and for sending a resultof the data processing to the processing apparatus; and the processingapparatus includes means for receiving the result of the data processingsent from the computer, and for operating according to the result of thedata processing thus received.

[0017] In one preferred embodiment, each of the processing apparatusesincludes measuring means for measuring a result of a treatment of theobject performed by each of the processing apparatuses, and wherein aresult of a measurement by the measuring means is capable of being sentfrom each of the processing apparatuses to the computer through thecommunication medium.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018]FIG. 1 is a diagram showing a structure of a processing system inone embodiment of the present invention;

[0019]FIG. 2 is a drawing showing an example of a structure of a CVDapparatus shown in FIG. 1;

[0020]FIG. 3 is a drawing showing an arrangement of zones in a reactiontube;

[0021]FIG. 4 is a block diagram showing an example of a structure of acontroller shown in FIG. 2;

[0022]FIG. 5 shows examples of temperature recipes;

[0023]FIG. 6 is a block diagram showing an example of a structure of acontrol computer shown in FIG. 1;

[0024]FIG. 7 is a table showing an example of a management table storedin an apparatus-DB (database) of FIG. 6;

[0025]FIG. 8 is a chart showing calibration procedures at the initialsetting of the processing system;

[0026]FIG. 9 is a chart for explaining a model calibration procedure;

[0027]FIG. 10 is a chart for explaining a recipe calibration procedure;

[0028]FIG. 11 shows measuring points on a wafer;

[0029]FIG. 12 is a chart for explaining a procedure performed by thecontrol computer in response to a notification of completion oftreatment which a processing apparatus outputs when it completes atreatment; and

[0030]FIG. 13 shows another operation of the processing system.

DESCRIPTION OF PERFERRED EMBODIMENTS

[0031] A processing system 1 according to the present invention will bedescribed below. As shown in FIG. 1, the processing system 1 is asemiconductor processing system, and is composed of a plurality ofprocessing apparatuses 3, plural numbers (j) of measuring apparatuses (5₁ to 5 _(j)), a control computer 7, and a network (LAN) 9 adapted tointerconnect these with each other. In a typical embodiment, theprocessing system is installed in a single building of a semiconductordevice manufacturing factory. However, the control computer 7 may beinstalled in a separate space from the factory building.

[0032] Each of the processing apparatuses 3 includes plural numbers (n)of CVD (Chemical Vapor Deposition) apparatuses 31 (31 ₁ to 31 _(n)),plural numbers (m) of oxidation apparatuses (32 ₁ to 32 _(m)), andplural numbers (i) of diffusion apparatuses (33 ₁ to 33 _(i)). Eachindex of the reference numerals indicates the apparatus number.

[0033] Each of the CVD apparatuses 31 (31 ₁ to 31 _(n)) hassubstantially the same structure, and accommodates objects to betreated, such as semiconductor wafers, to perform a film-formingtreatment on the objects by CVD. Each of the oxidation apparatuses 32(32 ₁ to 32 _(m)) has substantially the same structure, and oxidizessurface areas of the objects such as semiconductor wafers. Each of thediffusion apparatuses 33 (33 ₁ to 33 _(i)) has substantially the samestructure, and diffuses (dopes) impurities into the surface areas of theobjects such as semiconductor wafers. Each of the measuring apparatuses5 (5 ₁ to 5 _(j)) measures various numerical values representing theresults of the treatment of the object, e.g., the thickness of a filmformed on the object, and the concentration of a certain elementincluded in the diffusion area.

[0034] The structure of the CVD apparatus 31 will be described withreference to FIG. 2. The CVD apparatus 31 is of a batch type. The CVDapparatus 31 includes a reaction tube 302 of a double-tube structurehaving an inner tube 302 a and an outer tube 302 b. A tubular metallicmanifold 321 is disposed below the reaction tube 302.

[0035] In the reaction tube 302, a lot of, for example, 150 pieces ofsemiconductor wafers W (i.e., objects to be treated) are horizontallymounted on a wafer boat 323 while being vertically spaced at intervals.The wafer boat 323 is held on a cap 324 through a heat insulation tube325.

[0036] Five heaters 331-335 are arranged at different vertical positionsaround the reaction tube 302. Power controllers 336-340 supply electricpower to the heaters 331-335, respectively, to control the heaters331-335 separately. The reaction tube 302, the manifold 321 and theheaters 331-335 constitute a heating furnace. As shown in FIG. 3, thereaction tube 302 is divided into five zones each corresponding to eachheater 331-335.

[0037] As shown in FIG. 2, the manifold 321 has three gas supply pipes341, 342 and 343 for supplying gases into the inner tube 302 a. Processgases (precursor gases) for film-forming, such as dichlorosilane,ammonia, and nitrogen, and a carrier gas are supplied to the gas supplytubes 341, 342, and 343, through mass flow controllers (MFC) 344, 345,and 346, respectively. An exhaust pipe 327 is connected to the manifold321 for discharging gases in the reaction tube 302 through a gap betweenthe inner tube 302 a and the outer tube 302 b. The exhaust pipe 327 isconnected to a vacuum pump through a pressure regulating unit 328, etc.

[0038] Five thermal sensors (thermocouples) Sin1-Sin5 are verticallyaligned on an inner surface of the inner tube 302 a. Each thermal sensorSin1-Sin5 is covered with a quartz pipe (not shown) in order to preventmetallic contamination of the wafers W. The thermal sensors Sin1-Sin5are respectively arranged in the five zones shown in FIG. 3.

[0039] Five thermal sensors Sout1-Sout5 are vertically aligned on anouter surface of the outer tube 302 b. The thermal sensors Sout1-Sout5are also respectively arranged in the five zones shown in FIG. 3.

[0040] The CVD apparatus 31 has a controller 400 for controlling processparameters, such as temperature of process atmosphere, pressure and gasflow rate in the reaction tube 302. The controller 400 receives outputsignals of the thermal sensors Sin1-Sin5 and Sout1-Sout5, and outputscontrol signals to the power controllers 336-340 of the heaters 331-335,the pressure regulating unit 328 and the mass flow controllers 344-346.

[0041] Details of the structure of the controller 400 will be describedwith reference to FIG. 4. The controller 400 includes a control section411, a memory section 412, an I/O port 413, an control panel 414 and acommunication section 415.

[0042] The memory section 412 is constituted by a RAM, a ROM, a flashmemory, or a disk memory unit or the like. The memory section 412includes a model storage section 412 a, a recipe storage section 412 b,a program storage section 412 c, and a work area 412 d.

[0043] The model storage section 412 a stores a model (a mathematicalmodel; a high-order, multidimensional function), which is configured toestimate (i.e., calculate) the temperatures of the wafers W placed inthe respective zones based on the output signals (i.e., measuredtemperatures) of the thermal sensors Sin1-Sin5 and Sout1-Sout5, and theinstruction values sent to the power controllers 336-340 (i.e., thevalues corresponding to electric power supplied by the power controllers336-340 to the heaters 331-335), and is also configured to determineelectric power to be supplied to the heaters 331-335 so that eachestimated temperature coincide with a target value. Such a model isdisclosed in, for example, the U.S. Pat. No. 5,517,594, and can be usedherein.

[0044] The recipe storage section 412 b stores process recipes definingtreatment procedures for different sorts of the film-forming treatmentsperformed by each CVD apparatus 31. Each process recipe includes atemperature recipe which defines a desired temperature change to whichthe wafers W to be processed is subjected. The temperature recipes canbe expressed by temperature-time curves as shown in FIGS. 5(a) to 5(c).In a conventional processing apparatus of a batch type, a singletemperature recipe is prepared for all the wafers W. However, in thisembodiment, previously coordinated temperature recipes are prepared forevery zone shown in FIG. 3, so that the treatment achieves in-planeuniformity in each wafer W and uniformity between the wafers W.

[0045]FIG. 5(a) shows an example of the temperature recipe forperforming a film-forming treatment while maintaining the temperature ofthe wafers W constant. FIG. 5(b) shows an example of a temperaturerecipe for performing a film-forming treatment while lowering thetemperature of the wafers W. FIG. 5(c) shows an example of a temperaturerecipe for performing a film-forming treatment while raising thetemperature of the wafers W. In the event that the film-formingtreatment is performed while maintaining the temperature of the wafer Wconstant in accordance with the recipe shown in FIG. 5(a), thefilm-forming treatment is carried out while achieving uniformtemperature on the entire surface of the wafer W. In the event that thefilm-forming treatment is performed while lowering the temperature ofthe wafer W in accordance with the recipe shown in FIG. 5(b), thefilm-forming process is carried out with the temperature of the centerportion of the wafer W being higher than that of the peripheral portionof the wafer W. In the event that the film-forming treatment isperformed while raising the temperature of the wafer W in accordancewith the recipe shown in FIG. 5(c), the film-forming treatment iscarried out with the temperature of the center portion of the wafer Wbeing lower than that of the peripheral portion of the wafer W.

[0046] The program storage section 412 c stores programs such as anoperation control program for the control section 411. The work area 412d functions as a work area or the like of the control section 411.

[0047] The I/O port 413 supplies signals measured by the thermal sensorsSin1-Sin5 and Sout1-Sout5 to the control section 411, and outputscontrol signals outputted by the control section 411 to the powercontrollers 336-340, the mass flow controllers 344-346 and the pressureregulating unit 328, etc. The control panel 414 is connected to the I/Oport 413. The control panel 414 includes a display section and anoperating section, displays images provided by the control section 411,and gives instructions of the user to the control panel 411 through theI/O port 413.

[0048] The communication section 415 communicates data between the CVDapparatuses 31 and the control computer 7 through the LAN 9. The controlsection 411 has a processor to operate in accordance with the operationcontrol program stored in the program storage section 412 c. In aspecific embodiment, the control section 411 obtains output values ofthe thermal sensors Sin1-Sin5 and Sout1-Sout5, and instruction valuessent to the power controllers 336-340 (i.e., the values corresponding tothe power supplied to the heaters 331-335), applies these values to themodel stored in the model storage section 412 a, and estimates thetemperature of the wafer W in each zone at predetermined time intervalsor at a substantially real time mode. The control pat 411 instructs thepower controllers 336-340 to control the electric power so that theestimated temperature coincides with the value specified by thetemperature recipe stored in the recipe storage section 412 b.

[0049] The control section 411 also gives instructions to the mass flowcontrollers 344-346 and the pressure regulating unit 328 to controlstarting and stopping of the supply of the precursor gases, flow ratesof the precursor gases, pressure in the reaction tube 302, and so on,according to the process recipe.

[0050] The oxidation apparatuses 32 and the diffusion apparatuses 33shown in FIG. 1 are also of a batch type. Similar to the CVD apparatus31, each of the oxidation apparatus 32 and the diffusion apparatus 33estimates the temperature of the wafers W based on values measured bythe thermal sensors, and controls the heaters so that the estimatedwafer temperature coincides with the temperature specified by thetemperature recipe to perform a predetermined treatment.

[0051] The control computer 7 manages all the processing apparatuses31-33 and all the measuring apparatuses 5, and performs controlprocesses, such as a management of the number of runs of each apparatus,a renewal (fine-tuning) of the model, and a renewal of the recipe.

[0052] An example of a structure of the control computer 7 will bedescribed with reference to FIG. 6. The control computer 7 is composedof a control section 71, a communication section 72, a display section73, an input section 74, an apparatus database (DB) 75, and a memorysection 76.

[0053] The communication section 72 communicates data between theprocessing apparatuses 31-33 and the measuring apparatuses 5 through theLAN 9. The display section 73 shows various data relating to the controlcomputer 7 to the user. The input section 74 inputs instructions fromthe user and data to the control section 71.

[0054] The apparatus-DB 75 comprises, for example, a hard disk device,and stores management tables in which data for managing the respectiveprocessing apparatuses of every sort are recorded. For example, as shownin FIG. 7, the data included in the management table for the CVDapparatuses 31 are: the apparatus-ID, the total number of treatments(i.e., the total number of treatments performed after the apparatus isinstalled); the number of treatments after the calibration of the model(i.e., the number of treatments after the last calibration of themodel); the model (i.e., the model currently stored in the apparatus),the number of treatments after the calibration of the recipe (i.e., thenumber of treatments after the last calibration of the recipe); therecipe (i.e., the recipe currently stored in the apparatus); a targetfilm thickness (i.e., a desired film thickness), and so on. In addition,the data in the management table includes a basic model commonly used bythe CVD apparatuses (i.e., a basic model commonly used in theapparatuses of the same specifications) and a basic recipe commonly usedby the CVD apparatuses (i.e., a common basic recipe for a film-formingprocess performed by the apparatuses of the same specifications underthe same condition).

[0055] The memory section 76 stores an operation program, etc. of thecontrol section 71, and functions as a work area of the control section71.

[0056] The control section 71 operates according to a control programstored in the memory section 76, and manages the whole processing system1. Especially in this embodiment, the control section 71 counts thenumber of treatments performed by each processing apparatus 31-33, andcalibrates (corrects) the models and recipes of each apparatus for itsproper operation every time when each apparatus has performed adesignated number of treatments. Details of the calibration process willbe described later.

[0057] Next, the operation of the processing system 1 will be described.

[0058] When each processing apparatus of the processing system 1 aredesigned, the basic model is designed based on the structure and thefeature of the processing apparatus 3. The basic model is designedcommonly to the apparatuses of the same design specifications, and doesnot reflect the differences in the actual structure between theapparatuses and the differences in operating environments where therespective apparatuses are used. Thus, when the basic model is usedexactly as it is, the wafer temperature estimated by using the model maybe different from the actual wafer temperature.

[0059] Similarly, when designing a process (treatment), a basic recipedefining treatment steps (processes) to be performed by each processingapparatus 3 is designed in order to obtain a desired treatment result(e.g., target film thickness, film quality, element concentration, andso on). The basic recipe is designed commonly to the apparatuses of thesame design for performing the same treatment, and does not reflectdifferences in the structures and operation environments of therespective apparatuses. Thus, when the basic recipe is used exactly asit is, the manufactured film or layer may have a component, a thicknessand an element concentration which are different from the desired ones.

[0060] Therefore, as shown in FIG. 8, when the processing system 1 isinstalled (for example), the basic model and the basic recipe aresequentially calibrated (customized) for each of the processingapparatuses 3, so that the estimated wafer temperature coincides withthe actual wafer temperature and that a desired treatment result isobtained.

[0061] The calibration of the CVD apparatuses 31 is described by way ofexample. As shown in FIG. 7, before calibration, the apparatus-ID ofeach CVD apparatus 31 is registered in the apparatus-DB 75 of thecontrol computer 7. The basic model and the basic recipe are alsoregistered in the apparatus-DB 75 as the model and the recipe for eachCVD apparatus 31. Then, the total number of treatments, the number oftreatments after the calibration of the model, and the number oftreatments after the calibration of the recipe are set to be zero.

[0062] Next, the procedure for calibrating the model is described withreference to FIG. 9. The operator of the control computer 7 designatesthe apparatus-ID and the sort of apparatus of the CVD apparatus 31, andgives an instruction to start the calibration of the model.

[0063] In response to the instruction, the control part 7 retrieves arecipe exclusively used for calibrating the model from the memorysection 76 (step S111). Then, the control section 71 sends aninstruction for starting the model calibration and the recipe forcalibration to the CVD apparatus 31 to be calibrated (step S112). TheCVD apparatus 31 to be calibrated receives the instruction and therecipe for calibration from the control computer 7, and temporarilystores the received recipe for calibration in the recipe storage section412 b (step S113).

[0064] The person in charge of treatment loads the wafers W in acassette, and places the cassette on a receiving section of the CVDapparatus 31. The control section 411 of the CVD apparatus 31 makes theapparatus transfer the wafers W onto the wafer boat 323, and then makesthe apparatus place the wafer boat 323 on the heat insulation tube 325,in response to the instruction from the control computer 7.

[0065] Thereafter, the control section 411 makes the apparatus perform atreatment (process) according to the recipe for calibration stored inthe recipe storage section 412 b (step S114). Specifically, the controlsection 411 obtains the outputs of the thermal sensors Sin1-Sin5 andSout1-Sout5, and the instruction values sent to the respective powercontrollers 336-340, in order to estimate the temperature of the wafer Win each zone based on the model (the basic model is used for the firsttime). The control section 411 then adjusts the instruction values to besent to the respective power controllers 336-340 so that the estimatedwafer temperature coincides with the temperature specified by the recipefor calibration. Then, the control section 411 makes the apparatussupply gases according to the recipe for calibration so as to perform afilm-forming treatment.

[0066] When the film-forming treatment is completed (step S115), thecontrol section 411 sends the control computer 7 a notification of thecompletion of the film-forming treatment (step S116). The controlcomputer 7 receives the notification and waits for receiving a measuredvalue from the measuring apparatuses 5 (step S117).

[0067] The person in charge of treatment takes the processed wafers Wout of the CVD apparatus 31 (step S118), sets the wafers W in therespective zones in the measuring apparatus 5 (step S118), designatesthe apparatus-ID of the CVD apparatus 31, and measures the filmthickness of the wafer W (step S119). The measuring apparatuses 5 sendthe measured film thickness with the apparatus-ID to the controlcomputer 7 (step S119).

[0068] The control section 71 of the control computer 7 compares themeasured film thickness sent from the measuring apparatuses 5 with thetarget film thickness which should be obtained under the conditiondefined by the recipe for calibration. Based on the comparison, thecontrol section 71 calibrates the model for the CVD apparatus registeredin the apparatus-DB 75 (step S121). Specifically, if the measured filmthickness is smaller than the target film thickness, the current modelis calibrated such that lower temperature is estimated by the model. Onthe other hand, if the measured film thickness is larger than the targetfilm thickness, the current model is calibrated (customized) such thathigher temperature is estimated by the model.

[0069] In this way, the film thickness obtained by the treatmentperformed according to the recipe for calibration is compared with thetarget film thickness, and the model is calibrated based on thedifference in the film thickness between the former and the latter sothat the model can estimate an appropriate temperature. The controlsection 71 writes the calibrated model in a column for the CVD apparatus31 of the apparatus-DB 75, and sends the calibrated model to the CVDapparatus 31 to be calibrated (step S122). The CVD apparatus 31 receivesthe calibrated model and overwrites the same in the model storagesection 412 a (step S123).

[0070] By repeating the above calibration procedures of the controlcomputer 7 and each of the CVD apparatuses 31 for a designated number oftimes, the basic model is tuned to reflect the characteristics of eachapparatus. After the first calibration, the calibration is performed byusing the model calibrated by the last calibration.

[0071] After the difference between the actual film thickness and theexpected film thickness becomes less than a predetermined value, andafter the designated number of calibration procedures are carried out,the calibration of the model is completed, and then the calibration(customization) of the recipe is started.

[0072] The calibration of the recipe will be described with reference toFIG. 10. The operator of the control computer 7 designates the apparatusto be calibrated, and instructs to start the calibration of the recipe.In response to the instruction, the control section 71 of the controlcomputer 7 sends an instruction to the CVD apparatus 31 to be calibrated(step S211). The CVD apparatus 31 receives the instruction from thecontrol computer 7 (step S212).

[0073] The person in charge of treatment loads the wafers W on acassette, and places the cassette on the receiving part of the CVDapparatus 31. The CVD apparatus 31 transfers the wafers W onto the waferboat 323, and then places the wafer boat 323 on the heat insulation tube325.

[0074] Then, the CVD apparatus 31 performs a process according to therecipe (at the first time, the basic recipe is used) stored in therecipe storage section 412 b (step S213). Specifically, the controlsection 411 obtains the outputs from the thermal sensors Sin1-Sin5 andSout1-Sout5, and the instruction values sent to the respective powercontrollers 336 to 340, in order to estimate the temperature of thewafer W in each zone based on the model. The control section 411 thenadjusts the instruction values to be sent to the respective powercontrollers 336-340 so that the estimated wafer temperature coincideswith the temperature specified by the recipe. Then, the control section411 makes the apparatus supply gases according to the recipe so as toperform a film-forming treatment.

[0075] When the film-forming treatment is completed (step S214), thecontrol section 411 sends a notification of the completion of thefilm-forming treatment to the control computer 7 (step S215). Thecontrol computer 7 receives the notification and waits for receiving ameasurement results relating to the processing apparatus (step S216).

[0076] The person in charge of treatment takes the processed wafers Wout of the CVD apparatus 31, sets the same in the measuring apparatuses5, and inputs the apparatus-ID of the CVD apparatus 31. Wafers W arepicked up from each of the five zones, and the film thickness ismeasured at a plurality of, e.g., nine locations for each wafer W, asshown in FIG. 11. The measuring apparatuses 5 send the measured filmthickness with the inputted apparatus-ID of the CVD apparatus 31 to thecontrol computer 7 (step S218).

[0077] The control section 71 of the control computer 7 receives themeasured value and stores the same in the memory section 76 (step S219).Then, the control section 71 calibrates the recipe based on the measuredvalue (step S220). Although the recipe may be calibrated by any givenmethod, the following calibration procedure is performed in thisembodiment.

[0078] First, an average film thickness of the wafers W picked up fromthe five zones is calculated, and the temperatures specified by all therecipes respectively assigned to the zones are corrected so that theaverage film thickness coincides with the target film thickness. Forexample, when the average film thickness is smaller than the target filmthickness, the process temperature specified by the recipes for all thezones is increased. On the other hand, when the average film thicknessis larger than the target film thickness, the process temperaturespecified by the recipes for all the zones is lowered.

[0079] Next, an average film thickness is calculated for each wafer Wpicked up form each zone, and the temperature specified by the recipefor each zone is corrected so that the average film thickness coincideswith the target film thickness. For example, when the average filmthickness of a wafer W picked up form one zone is smaller than thetarget film thickness, the process temperature specified by the recipefor the zone is increased. On the other hand, when the average filmthickness is larger than the target film thickness, the processtemperature specified by the recipe for the zone is lowered.

[0080] Third, the control section 71 corrects the recipe to reduce thein-plane ununiformity in the thickness of the film formed on the wafer Win each zones. As described above, with the apparatus structure shown inFIG. 2, the temperature is higher at the peripheral portion of the waferW than at the center portion, when raising the temperature of the waferW. On the other hand, the temperature is lower at the peripheral portionof the wafer W than at center portion, when lowering the temperature ofthe wafer W. In general, when performing a film-forming treatment,higher wafer temperature promotes the film-forming and thus results in athicker film, if the process conditions other than the wafer temperatureare equal.

[0081] In the event that the film formed on the wafer W picked up fromone zone is of a concave (cup) shape, that is, the film is thicker atthe peripheral portion of the wafer W and is thinner at the centerportion, uniform film thickness can be achieved if the relativetemperature at the peripheral portion of the wafer W is lower than thatwhen the concave film is formed. To this end, the temperature changerate (gradient of the line during the supply of the process gases shownin FIG. 5) during a film-forming treatment (during the supply of processgases) is changed. For example, in the recipe shown in FIG. 5(a), thetemperature recipe for the zone is corrected such that the gradient ofthe line during the supply of process gases is changed from zero tonegative value. In the recipe shown in FIG. 5(b), the temperature recipefor the zone is corrected such that the gradient of the line during thesupply of process gases is higher. In the recipe shown in FIG. 5(c), thetemperature recipe for the zone is corrected such that the gradient ofthe line during the supply of process gases is lower. On the other hand,in the event that the film formed on the wafer W picked up from one zoneis of a convex (cap) shape, that is, the film is thicker at the centerportion of the wafer W and is thinner at the peripheral portion, uniformfilm thickness can be achieved if the relative temperature at theperipheral portion of the wafer W is higher than that when the convexfilm is formed. To this end, the aforementioned correction in thetemperature change rate should be reversed.

[0082] In this manner, the control section 71 corrects or calibrates therecipe currently stored in the CVD apparatus 31 to be calibrated. Thecontrol section 71 overwrites the calibrated recipe in a recipe storagearea for the corresponding CVD apparatus 31 of the apparatus-DB 75, andsends the calibrated recipe to the CVD apparatus 31 to be calibrated(step S221). The control section 411 of the CVD apparatus 31 receivesthe calibrated recipe and overwrites the same in the recipe storagesection 412 b (step S222).

[0083] By repeating the calibration of the recipe for plural times, thebasic recipe common to all the CVD apparatuses 31 can be tuned toreflect the characteristics of each apparatus. After the firstcalibration, the calibration is performed by using the recipe calibratedby the last calibration.

[0084] After the difference between the film thickness thus formed andthe expected film thickness becomes less than a predetermined value, andafter the designated number of calibration procedures are repeated, thecontrol section 71 completes the calibration of the recipe, informs theoperator of the completion of the calibration of the recipe via thedisplay section 73, and informs the calibrated processing apparatus 3 ofthe completion of the calibration of the recipe through the LAN 9. Theprocessing apparatus 3 displays the completion of the calibration on thecontrol panel 414 to inform the person in charge of treatment of thecompletion of the calibration. Thus, the calibration procedures in theinitial setting are completed. Thereafter, the CVD apparatus 31 performsa normal operation (e.g., film-forming treatment on the product wafer).

[0085] The above-described calibration can be performed for the pluralprocessing apparatuses 3 in parallel. In the case where a new processingapparatus 3 is added to the processing system 1 shown in FIG. 1, thecalibration is performed only for the newly added processing apparatus3. At this time, other processing apparatuses 3 can perform a normaloperation.

[0086] The operation of the processing system 1 when each processingapparatus 3 performs a normal operation will be described with referenceto FIG. 12. During the normal operation, upon a completion of onetreatment, the control section 411 of each processing apparatus 3 sendsa notification of the completion of the treatment to the controlcomputer 7.

[0087] In response to the notification of the completion of thetreatment, the control section 71 of the control computer 7 adds “one”to the total number of treatments performed by the apparatus, adds “one”to the number of treatments performed by the apparatus after thecalibration of the model, and adds “one” to the number of treatmentsperformed by the apparatus after calibration of the recipe, each “numberof treatments” being stored in the management table (FIG. 6) of theapparatus-DB 75 (step S21). Then, the control section 71 judges whetheror not the number of treatments after the calibration of the modelreaches a previously determined value (e.g., 13 times) (step S22).

[0088] If it reaches, the control section 71 judges that the model ofthe processing apparatus must be calibrated, and informs the operator ofthe fact through the display section 73.

[0089] The following operations are basically identical with thecalibration procedure of the initial setting as shown in FIG. 9. Thecontrol computer 7 retrieves the recipe for calibrating the processingapparatus 3 to be calibrated from the memory section 76 (step S111), andsends an instruction for starting the calibration of the model and alsosends the recipe for calibration to the processing apparatus 3 to becalibrated (step S112). The processing apparatus 3 receives theinstruction and the recipe for calibration from the control computer 7,and stores the recipe for calibration in the recipe storage section 412b (step S113). Then, the processing apparatus 3 to be calibratedperforms a film-forming treatment according to the recipe forcalibration stored in the recipe storage section 412 b (step S114).

[0090] When the film-forming process is completed (step S115), thecontrol section 411 sends a notification of the completion of thefilm-forming treatment to the control computer 7 (step S116). Thecontrol computer 7 receives the notification, and waits for receiving ameasurement result from the measuring apparatuses (step S117).

[0091] The person in charge of treatment sets the processed wafers W inthe measuring apparatuses 5, and designates the apparatus-ID of theprocessing apparatus 3, and the treatment result is measured. Themeasuring apparatuses 5 send the measured film thickness and theapparatus-ID to the control computer 7 (step S119).

[0092] The control section 71 of the control computer 7 receives thefilm thickness thus sent (step S120), and performs the calibration ofthe model (step S121). The control section 71 overwrites the calibratedmodel in a model area for the processing apparatus 3 in the managementtable in the apparatus-DB 75, and sends the calibrated model to theprocessing apparatus 3 to be calibrated (step S122).

[0093] The processing apparatus 3 receives the calibrated model andoverwrites the same in the model storage section 412 a.

[0094] Upon completion of the above calibration, the control computer 7resets the column of the number of treatments after the calibration ofthe model for the processing apparatus in the management table recordedin the apparatus DB 75 to be zero (FIG. 12, Step S24).

[0095] Then, the control section 71 judges whether or not the number oftreatments performed by the apparatus after the calibration of therecipe stored in the management table reaches a predetermined value(step S25).

[0096] If it does not reach, the control section 71 completes theprocessing to be performed in response to the notification of thecompletion of the treatment. If it reaches, the control section 71judges that the recipe for the processing apparatus 3 must becalibrated, and informs the operator of the needs of the calibration viathe display section 73.

[0097] The following operations are basically identical with the recipecalibration procedure in the initial setting shown in FIG. 10. Thecontrol section 71 of the control computer 7 sends an instruction forstarting the calibration of the recipe to the processing apparatus 3 tobe calibrated (step S211).

[0098] The processing apparatus 3 receives the instruction from thecontrol computer 7 (step S212), and then performs a treatment accordingto the recipe for calibration stored in the recipe storage section 412 b(step S213).

[0099] Upon completion of the treatment, the control section 411 sends anotification of the completion of the film-forming treatment to thecontrol computer 7 (step S214). The control computer 7 receives thenotification, and waits for receiving a measurement result from themeasuring apparatuses 5 (step S216).

[0100] The person in charge of treatment sets the treated or processedwafers W in the measuring apparatuses 5, and designates the apparatus-IDof the processing apparatus 3 to measure the treatment result. Themeasuring apparatuses 5 send a measured film thickness and theapparatus-ID to the control computer 7 (step S218). The wafers W to bemeasured, and the positions and the number of the measuring points areidentical with those designated at the initial setting.

[0101] The control section 71 retrieves the currently stored recipe ofthe processing apparatus 3 to be calibrated from the management table.Based on the measured values, the control section 71: (1) calibrates therecipes for all the zones such that the average film thickness of allthe wafers W is equal to the target film thickness; (2) calibrates eachrecipe for each zone such that the average film thickness of a wafer Win each zone is equal to the target film thickness; and (3) calibrateseach recipe for each zone such that the film thickness differencebetween the wafers W is reduced and the film thickness distribution ineach wafer W is narrowed (step S220).

[0102] In this way, the control computer 7 calibrates the recipe of theprocessing apparatus 3, overwrites the same in the recipe storage areafor the corresponding processing apparatus in the management tablerecorded in the apparatus-DB 75, and sends the calibrated recipe to theprocessing apparatus 3 to be calibrated (step S221).

[0103] The processing apparatus 3 receives the calibrated recipe andstores the same in the recipe storage section (step S223).

[0104] Upon completion of the above calibration, the control computer 7resets the column of the number of treatments after the calibration ofthe recipe for the processing apparatus in the management table recordedin the apparatus DB 75 to be zero (FIG. 12, step S27).

[0105] As described above, the processing system 1 performs acentralized control of the plurality of processing apparatuses 3 bymeans of the control computer 7. Thus, the management of the apparatusesis significantly promoted as compared with the conventional managementmethod. As the control computer 7 handles high-load data processing suchas the calibration of the model and the calibration of the recipe,structures of software and hardware of each processing apparatus 3 canbe simplified. In addition, due to the aforementioned calibrationprocedure, the treatment can be properly performed and a desired qualitycan be obtained.

[0106] The present invention is not limited to the above embodiment, andvarious modifications and applications are possible. For example, in theabove embodiment, a treatment is carried out and then a model iscalibrated based on the treatment result. However, for example, dummywafers having thermo sensors incorporated therein may be placed in therespective zones, and the temperature of each wafer may be directlymeasured and recorded. Then, the model may be calibrated so that themeasured actual temperature coincides with the temperature which isestimated by using the model.

[0107] In the above embodiment, the model and the recipe are calibratedby performing a treatment exclusively for the calibration, every timewhen designated number of treatments has been carried out. However, itis possible to calibrate the model or the recipe, while performing ausual process. For example, in performing a usual process, dummy wafershaving thermo sensors incorporated therein and product wafers arepositioned in the respective zones, and the temperature of each wafermay be directly measured and recorded. Then, the control computer 7 maycalibrate the model so that the temperature estimated by using the modelcoincides with the measured actual temperature, and renews the model ofthe processing apparatus 3 before the next treatment starts.

[0108] Wafers W may be sampled from the product wafers subjected to ausual treatment in each zone. The film thickness of each sample wafermay be measured, and then the control computer 7 may calibrate the modelby using the measured value, and may renew the model or recipe of theprocessing apparatus 3 before the next treatment starts. According tothis method, it is possible to calibrate the model and the recipewithout halting the processing apparatus 3.

[0109] In the above embodiment, although the control computer 7calibrates the model and the recipe, the control computer 7 can performother data processing. For example, a certain computing functionpossessed by the plurality of processing apparatuses may be assigned tothe control computer 7. As shown in FIG. 13, when the person in chargeof treatment operates the control panel 414 (see, FIG. 4) of theprocessing apparatus 3 to input any given data, the data and theapparatus-ID are sent to the control computer 7 through the LAN 9 (stepS311). The control computer 7 analyzes the inputted data (step S312),and performs data processing based on the inputted data (step S313)(data processing such as computing operation for changing the settingsof the apparatus). The result is returned to the processing apparatus 3.The data received by the processing apparatus 3 are utilized to changethe settings of the processing apparatus 3 or to control the processingapparatus, and are displayed on the control panel 414. Also in thiscase, constitutions of the respective apparatuses can be simplified. Inaddition, the person in charge of treatment can operate the respectiveprocessing apparatuses without being aware of the existence of thecontrol computer.

[0110] In the above embodiment, the measuring apparatuses are separatedfrom the processing apparatuses 3. However, the measuring apparatus 5may be incorporated in the processing apparatus 3. According to this,the measurement result for the object to be treated by the measuringapparatus 5 can be sent from the processing apparatus 3 to the controlcomputer through the LAN 9. When sending the treatment result, anapparatus-ID can automatically be attached to the treatment result data,which further saves labor.

[0111] In the above embodiment, although the LAN 9 is exemplified as acommunication medium, the constitution of the communication means isoptionally determined. For example, it is possible to communicate dataand instructions among the apparatuses through a record medium such as aflexible disc and a flash memory.

[0112] In the above embodiment, although a semiconductor wafer isexemplified as an object to be treated, the object may be a liquidcrystal display element and a glass substrate of PDP.

1. A processing system comprising: a plurality of processing apparatuseseach including treatment means for treating an object, memory means forstoring control data for controlling the treatment means, and controlmeans for controlling the treatment means according to the control data;and a computer arranged separately from the processing apparatuses andadapted to communicate data including the control data with theprocessing apparatuses through a communication medium, the computerincluding calibration means for calibrating the control data forcontrolling each of the processing apparatuses based on a result of atreatment of the object performed by each of the processing apparatusesinputted into the computer.
 2. The processing system according to claim1, wherein the control means of each of the processing apparatuses isconfigured to receive the control data calibrated by the calibrationmeans of the computer through the communication medium, configured tostore the calibrated control data in the memory means, and configured toperform a treatment according to the calibrated control data.
 3. Theprocessing system according to claim 1, wherein: the computer includesmemory means for storing control data corresponding to each of thecontrol data stored in the memory means of each of the processingapparatuses; and the computer is configured to perform a procedure, whencalibrating the control data for one of the processing apparatuses, theprocedure including the steps of: retrieving the control data for saidone of the processing apparatuses stored in the memory means of thecomputer; calibrating the retrieved control data based on a result of atreatment of the object performed by said one of the processingapparatuses; storing the calibrated control data in the memory means ofthe computer; and sending the calibrated control data to said one of theprocessing apparatuses through the communication medium, and making thememory means of said one of the processing apparatuses store thecalibrated control data.
 4. The processing system according to claim 1,further comprising a measuring apparatus adapted to measure a result ofa process performed by the processing apparatus, wherein the computer isconfigured to communicate data with the measuring apparatus through thecommunication medium, whereby the result of the treatment is inputtedinto the computer through the communication medium.
 5. The processingsystem according to claim 1, wherein: the treatment means of each of theprocessing apparatuses includes a heating furnace adapted to heat theobject contained therein, and a plurality of thermal sensors arranged atthe heating furnace; the control data include a model for estimatingtemperature of the object based on outputs of the thermal sensors, and arecipe defining change in temperature of the object during thetreatment; the memory means of each of the processing apparatuses isconfigured to store the model and the recipe; and the control means ofeach of the processing apparatuses is configured to estimate thetemperature of the object placed in the heating furnace based on theoutputs of the thermal sensors by using the model stored in the memorymeans, and configured to control the heating furnace based on theestimated temperature so that the temperature of the object is coincidewith a temperature specified by the recipe stored in the memory means.6. The processing system according to claim 5, wherein the computer isconfigured to perform a procedure, when calibrating the model for one ofthe processing apparatuses, the procedure including the steps of:sending a recipe for calibrating the model to said one of the processingapparatuses; making said one of the processing apparatuses perform atreatment of the object according to the recipe for calibrating themodel; and calibrating the model by the calibration means based on aresult of the treatment of the object.
 7. The processing systemaccording to claim 6, wherein the computer is configured to calibratethe model based on a measurement of an actual temperature of the objectduring the treatment being performed.
 8. The processing system accordingto claim 1, wherein: each of the processing apparatuses is configured tosend a notification of completion of the process of the object to thecomputer; and the computer is configured to count the number oftreatments performed by each of the processing apparatuses according tothe notification, and configured to correct the control data at everytime when a designated number of treatments has been performed by eachof the processing apparatuses after last calibration of the controldata.
 9. The processing system according to claim 1, wherein: theprocessing apparatus has means for requesting the computer to perform adata processing; the computer includes means for performing the dataprocessing in response to a request received from the processingapparatus, and for sending a result of the data processing to theprocessing apparatus; and the processing apparatus includes means forreceiving the result of the data processing sent from the computer, andfor operating according to the result of the data processing thusreceived.
 10. The processing system according to claim 1, wherein eachof the processing apparatuses includes measuring means for measuring aresult of a treatment of the object performed by each of the processingapparatuses, and wherein a result of a measurement by the measuringmeans is capable of being sent from each of the processing apparatusesto the computer through the communication medium.